Fernando J. Corbató

Amongst many awards, he received the Turing Award in 1990, "for his pioneering work in organizing the concepts and leading the development of the general-purpose, large-scale, time-sharing and resource-sharing computer systems".

The first timesharing system he was associated with was known as the MIT Compatible Time-Sharing System, an early version of which was demonstrated in 1961. The experience gained led to a second project, Multics, which was adopted by Honeywell. Multics, while not particularly commercially successful in itself, directly inspired Ken Thompson to develop Unix, the direct descendants of which are still in extremely wide use; it also served as a model for every other subsequent operating system design.